| 1. |
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| 2. |
- Huang, Juan, et al.
(författare)
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Differential metabolic profiles of ginsenosides in artificial gastric juice using ultra-high-pressure liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometry
- 2022
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Ingår i: BMC Biomedical chromotography. - : John Wiley & Sons. - 0269-3879 .- 1099-0801. ; 36:12
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Tidskriftsartikel (refereegranskat)abstract
- Ginsenosides have poor oral bioavailability and undergo rapid biological transformation in the complex gastrointestinal environment. Most studies on the metabolism of ginsenosides have focused on gut bacteria, yet gastric juice remains a nonnegligible factor. Metabolic profiles of ginsenoside monomers formed in artificial gastric juice were separately investigated and qualitatively identified using ultra-high-pressure liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometry (UHPLC-LTQ-Orbitrap MSn). A common pattern of their metabolic pathways was established, showing that ginsenosides were transformed via deglycosylation, hydration, and dehydration pathways. Two major structure types, 20(S), 20(R)-protopanaxatriols and 20(S), 20(R)-protopanaxadiols, basically shared similar transformation pathways and yielded deglycosylated, hydrated, and dehydrated products. Fragmentation patterns of major ginsenosides were also discussed. Consequently, gastric juice, as the primary link in ginsenoside metabolism and as important as the intestinal flora, produces considerable amounts of degraded ginsenosides, providing a partial explanation for the low bioavailabilities of primary ginsenosides.
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| 3. |
- Liang, Pu-Lin, et al.
(författare)
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Three polymethoxyflavones from the peel of Citrus reticulata "Chachi" inhibits oxidized low-density lipoprotein-induced macrophage-derived foam cell formation
- 2022
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Ingår i: Frontiers in Cardiovascular Medicine. - : Frontiers Media S.A.. - 2297-055X. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Foam cell formation is the hallmark of the development and progression of atherosclerosis. The aim of this study was to investigate the regulatory effects of three polymethoxyflavones (PMFs), namely, tangeretin (TAN), 5,6,7,3 ',4 ',5 '-hexamethoxyflavone (HxMF), and 3,5,6,7,8,3 ',4 '-heptamethoxyflavone (HpMF) on macrophage-derived foam cell formation and to further explore the molecular mechanisms. The RAW264.7 macrophage-derived foam cell model was successfully induced by oxidized low-density lipoprotein (ox-LDL) (80 mu g/ml). It showed that TAN, HxMF, and HpMF alleviated ox-LDL-induced NO release while also inhibiting the expression of IL-1 beta, IL-6, and TNF-alpha in RAW264.7 cells. Uptake of excess ox-LDL was inhibited by TAN, HxMF, and HpMF, resulting in the reduction of its foam cell formation. Moreover, TAN, HxMF, and HpMF promoted HDL-mediated cholesterol efflux. Western blot experiment showed that TAN, HxMF, and HpMF inhibited the expression of scavenger receptor class A type I (SRA1) and cluster of differentiation 36 (CD36), while upregulating peroxisome proliferator-activated receptor gamma (PPAR gamma), liver X receptor alpha (LXR alpha), phospholipid ATP-binding cassette transporter G1 (ABCG1), and scavenger receptor class B type I (SRB1) expression. Together, our findings suggested that PMFs inhibited foam cell formation might inhibit lipid uptake via downregulating SRA1/CD36 expression and promote cholesterol efflux from foam cells via upregulating PPAR gamma/LXR alpha/ABCG1/SRB1 expression. This antiatherosclerotic activity is expected to provide new insights into the development of healthcare uses for PMFs.
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| 4. |
- Lu, R.S., et al.
(författare)
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A ring-like accretion structure in M87 connecting its black hole and jet
- 2023
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Ingår i: Nature. - 0028-0836 .- 1476-4687. ; 616:7958, s. 686-690
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Tidskriftsartikel (refereegranskat)abstract
- The nearby radio galaxy M87 is a prime target for studying black hole accretion and jet formation1,2. Event Horizon Telescope observations of M87 in 2017, at a wavelength of 1.3 mm, revealed a ring-like structure, which was interpreted as gravitationally lensed emission around a central black hole3. Here we report images of M87 obtained in 2018, at a wavelength of 3.5 mm, showing that the compact radio core is spatially resolved. High-resolution imaging shows a ring-like structure of [Formula: see text] Schwarzschild radii in diameter, approximately 50% larger than that seen at 1.3 mm. The outer edge at 3.5 mm is also larger than that at 1.3 mm. This larger and thicker ring indicates a substantial contribution from the accretion flow with absorption effects, in addition to the gravitationally lensed ring-like emission. The images show that the edge-brightened jet connects to the accretion flow of the black hole. Close to the black hole, the emission profile of the jet-launching region is wider than the expected profile of a black-hole-driven jet, suggesting the possible presence of a wind associated with the accretion flow.
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| 5. |
- Chen, Xue-Lian, et al.
(författare)
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Polyphenolics from Syzygium brachythyrsum Inhibits Oxidized Low-Density Lipoprotein-Induced Macrophage-Derived Foam Cell Formation and Inflammation
- 2022
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Ingår i: Foods. - : MDPI. - 2304-8158. ; 11:21
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Tidskriftsartikel (refereegranskat)abstract
- Evidence suggests that the immunomodulatory property of polyphenols may also contribute to the reduction of cardiovascular risk. In the present study, we investigated the polyphenol extraction (PE) from Syzygium brachythyrsum, a functional food resource in south China, regarding the protective effect on inhibiting foam cell formation and the underlying molecular mechanism based on an ox-LDL-induced RAW264.7 macrophage model. The results of Oil Red O staining, Dil-ox-LDL fluorescent staining, and cholesterol efflux experiments showed that PE, and its two phenolics brachythol B (BB) and ethyl gallate (EG), significantly inhibited the foam cell formation, which may be associated with reducing the expression of SR-A1 and CD36 while increasing expression of SR-B1, ABCG1, and PPAR gamma. In addition, BB and EG also reduce the inflammatory response by down-regulating the expression of NF-kappa B and MAPK signal pathway proteins, thereby inhibiting the expression of inflammatory factors. Altogether, PE and its two components BB and EG attenuated foam cell formation and macrophage inflammation response.
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| 6. |
- Guan, Jian-Yue, et al.
(författare)
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Cooperation influenced by the correlation degree of two-layered complex networks in evolutionary prisoner's dilemma games
- 2010
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Ingår i: Chinese Physics B. - : Institute of Physics (IOP). - 1674-1056. ; 19:2
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Tidskriftsartikel (refereegranskat)abstract
- An evolutionary prisoner's dilemma game is investigated on two-layered complex networks respectively representing interaction and learning networks in one and two dimensions. A parameter q is introduced to denote the correlation degree between the two-layered networks. Using Monte Carlo simulations we studied the effects of the correlation degree on cooperative behaviour and found that the cooperator density nontrivially changes with q for different payoff parameter values depending on the detailed strategy updating and network dimension. An explanation for the obtained results is provided.
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| 7. |
- Huang, Zi-Gang, et al.
(författare)
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Role of collective influence in promoting cooperation
- 2008
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Ingår i: Europhysics letters. - Les Ulis : European Physical Society. - 0295-5075 .- 1286-4854. ; 84:5, s. 50008-
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Tidskriftsartikel (refereegranskat)abstract
- The collective influence on the individuals' behavior have attracted much attention, and interesting phenomena such as social facilitation and social loafing have been studied. In this paper, we consider how the collective influence affects the evolution of cooperation in a structured population of individuals who nourish and benefit from public goods in groups. Individuals are supposed to distribute endowments to different groups to nourish the corresponding public goods. The collective influence is indicated by a tunable parameter α, with larger α corresponding to the players' higher preference to contribute more to the larger groups, which is similar to the social-facilitation effect in the real world, whereas, with smaller α corresponding to individuals' contrary preference, i.e., the social-loafing effect. Interestingly, we find that the heterogeneity of public-goods setting favors cooperation. Furthermore, the system where social loafing occurs performs better than that with social facilitation, in the case of heterogeneous formation.
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| 8. |
- Li, Wei, et al.
(författare)
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Heat transfer to aviation kerosene flowing upward in smooth tubes at supercritical pressures
- 2015
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Ingår i: International Journal of Heat and Mass Transfer. - : Elsevier BV. - 0017-9310. ; 85, s. 1084-1094
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Tidskriftsartikel (refereegranskat)abstract
- This study experimentally investigated convective heat transfer performances of China RP-3 kerosene flowing in a vertical upward tube under supercritical pressures. Effects of mass flux, heat flux, pressure and inlet temperature on the heat transfer performance were given in detail. The influences of buoyancy and flow acceleration under different flow conditions were discussed as well. It was found that the inner wall temperature varies non-linearly at different mass fluxes. Heat transfer is improved when the fuel temperature is around the critical temperature. The heat transfer coefficient increases as heat flux or inlet temperature increases, while increase in inlet pressure reduces heat transfer coefficient. Besides, as nanofluids generally have higher thermal conductivity compared to their corresponding base fluids (i.e. kerosene), the heat transfer characteristics of Fe3O4-kerosene nanofluid was also investigated. It was found that the addition of nanoparticles tends to deteriorate the heat transfer performance of nanofluids flowing in a vertical tube under supercritical pressure. As the particle content increases, the heat transfer coefficient decreases due to the modification of the inner wall surface by the nanoparticles. (C) 2015 Elsevier Ltd. All rights reserved.
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| 9. |
- Wang, Sheng-Jun, 1981-, et al.
(författare)
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Influence of synaptic interaction on firing synchronization and spike death in excitatory neuronal networks
- 2008
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Ingår i: Physical Review E. Statistical, Nonlinear, and Soft Matter Physics. - New York : American Physical Society through the American Institute of Physics. - 1063-651X .- 1095-3787. ; 78:6, s. 061906-
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Tidskriftsartikel (refereegranskat)abstract
- We investigate the influence of efficacy of synaptic interaction on firing synchronization in excitatoryneuronal networks. We find spike death phenomena: namely, the state of neurons transits from the limit cycleto a fixed point or transient state. The phenomena occur under the perturbation of an excitatory synapticinteraction, which has a high efficacy. We show that the decrease of synaptic current results in spike deaththrough depressing the feedback of the sodium ionic current. In the networks with the spike death property thedegree of synchronization is lower and insensitive to the heterogeneity of neurons. The mechanism of theinfluence is that the transition of the neuron state disrupts the adjustment of the rhythm of the neuronsoscillation and prevents a further increase of the firing synchronization.
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